chasb4570

On Veteran's day this past year, we went on a run to Prescott, AZ. The gauge was showing 7/8 full when it dropped to zero, check gauges light came on as well as low fuel warning. Drove the rest of the trip okay until about seven miles from home when the car died. To make a long story shorter, turns out, out of fuel even though when clearing code, there was just under half a tank still available. I put in two bottles of the Techron 20 gallon additive and filled back up. The car has seen little use since, with the Techron mix still in the tanks. Yesterday I was tinkering under the hood with the engine running. The gauge had been showing just over 1/4 available. When I shut off the engine, the gauge had dropped to zero again, I cleared the code and the gauge went back to just over 1/4 tank. Took the wife out to dinner for her birthday no less and on the way home, with the gauge till showing fuel available, car ran out of fuel.
I have read info about the sulphur build up etc., but have never read about anyone actually running out of fuel after resetting the code and the gauge still showing fuel in tanks. And yes, when I fill the car up, the gauge has been true as to the amount of fuel still in the tanks. 2004 coupe with 20,000 on the clock. NO fuel smell when tanks are filled.
Planning a few trips this spring and this is not going to work well. Any thoughts or ideas? Help Please.
Thanks
Chas

Ed Prov

I have an '02 that my kids bought me for my 70th b'day that had
the same problem. 8vette7 is dead-on. Fuel system is designed to
siphon from passenger side to driver side. In theory the passenger
side is drained first. When the computer sees driver side level drop
below passenger side level it fails the gauge to empty.

I bought a replacement for the passenger side pump but delayed
changing it because I didn't want to deal with draining the 7-8 gallons
in the tank. Meanwhile, I kept putting Techron in at every fill-up (btw,
Costco has great pricing on case of Techron). After 3 months of this,
problem went away and has not recurred. Still use Techron (every 4th
fill-up). Never used replacement fuel pump.

Ed

midnight01

I believe the code is P1431 and part of the GM PCM flash "Fix" was to disable the code from tripping the cel light
Mine just did it after a long trip so I went and bought a replacement jet pump for the passenger side. After reading what others were doing I filled up with Chevron Techron gas and threw a techron fuel system cleaner concentrate plus in the tank and the next morning the gauge worked again although now it is actually working better then it ever did as it actually changes if I go around a corner or if I am on a hill it either goes up or down pretty quickly.

If you dont have a Chevron station get yourself 2 bottles of the techron concentrate plus and fill your tank and use 1 then drive till low and do it again. I would have never thought that would fix it but it did.

I now have a 241.00 replacement jet pump that will collect dust until it fails entirely.